On one of the Drupal sites I was developing, admin pages were getting (unbearably) slow-- about 30 seconds to load each page. Using the Google, I found a couple of articles that pointed the finger at the Update Status module:
Looking at the "Recent Log Entries" report, I could see that there was an "Attempted to fetch information about all available new releases and updates" entry for each page view. This meant that Update Status was checking the status of all my modules with each page load even though I had it set to check weekly. That would definitely slow things down a bit! Deactivating the "Update Status" module fixed the slowdown, but I really wanted to have that functionality. Turning the module back on, just made the site crawl again.
What fixed it for me was deactivating the "Update Status" module then uninstalling it from the "Build -> Modules -> Uninstall" tab. This removes all of its module-related settings from the database. Then, when I activated "Update Status" again, all was well.
This blog post was originally published on embiggen.net